Twenty-first century military medals should reflect 21st-century conflicts. But the Pentagon must never slight the risk of life and limb in combat.

Physical risk is the central issue in recent disputes over the Purple Heart and the recognition of drone pilots. The controversies have helped prompt Defense Secretary Chuck Hagel to order a yearlong study of how the Pentagon awards its ribbons and medals.

It’s a timely review. Many existing practices have their roots in the World War II era, long before the ambiguities of the war on terror.

Hagel’s predecessor, Leon Panetta, stirred up a hornets nest a year ago when he created a new Distinguished Warfare Medal to honor “the extraordinary achievements that directly impact on combat operations but that do not involve acts of valor or physical risks that combat entails.”

Recipients would include drone pilots who — though located as far away as Nevada — had distinguished themselves in supporting ground combat operations in Afghanistan.

The medal, since cancelled by Hagel, antagonized American combat veterans. They didn’t object to honoring the pilots; they objected to Panetta’s plan to give the new medal precedence over the Purple Heart, given to the wounded, and the Bronze Star for valor in combat.

American Legion Commander James Koutz put it rather well: “There’s a fundamental difference between those who fight remotely, or via computer, and those fighting against an enemy is who is trying to kill them.”

The Purple Heart dispute is the same issue in reverse: failure to decorate troops who were in harm’s way. These were the 12 soldiers killed and 31 wounded in 2009 when a secret jihadist — Maj. Nidal Malik Hasan — opened fire on everyone in sight at Fort Hood, Texas.

The Pentagon classified this as “workplace violence,” which is certainly an understatement. This label disqualified the victims from the Purple Heart, which is awarded for wounds “received in action against an enemy” or “from an international terrorist attack.”

Hasan, the logic went, was a domestic “lone wolf,” not part of an international organization.

But the circumstances and the nature of terrorism don’t support such a clear line. Hasan had frequently communicated via email with an al-Qaida firebrand in Yemen prior to the attack. At his trial, he described himself as a mujahedeen who’d “switched sides” to the terrorists.

Hasan didn’t exactly have orders from Osama bin Laden, but he was in contact and in sync with al-Qaida.

This kind of lone wolfism is one of the faces of modern international terrorism, and it’s going to produce more military casualties. Awards for wounds and valor should reflect that reality. A soldier injured by any jihadist, foreign or domestic, bleeds just as red.